Some packages have been used in transporting products. For transporting fluid consumed in large amounts for business use, drum cans have previously been used. However, the drum cans have the problems that high cost is required for treatment after use, and that empty cans themselves are voluminous to cause them to occupy wide space during storage.
Recently, the so-called bag-in-box system has been widely used as packaging not voluminous after use of the contents and recyclable. In this system, a flexible plastic bag is filled with the fluid contents, and the resulting filled bag is housed in a cardboard box for avoiding shock.
In the bag-in-box system, the cardboard box can be folded after use and stored in a compact form, and is also recyclable. The plastic bag can be easily discarded, for example, burned, because of its non-voluminousness. However, there has been the problem that the contents charged into the plastic bag is difficult to be taken out of the bag because of lack of the self-sustaining of the bag itself, even if the bag is housed in the cardboard box.
As a technique for efficiently taking out fluid charged into a plastic bag, a bag equipped with a special discharge outlet and a pump having a suction mouth brought into engagement with this special discharge outlet have been proposed. However, this technique has the disadvantage that the bag equipped with the special discharge outlet is expensive.
Further, when the contents are high-viscosity fluid such as jam, honey, mayonnaise, ketchup, pur F, adhesives, paints and ink, even this method has a limitation on suction force of the pump, and therefore it is impossible to smoothly suck the contents.
Furthermore, even according to this method, it is difficult to take out the contents remaining in a bottom of the bag, and the contents adhered to the inside of the bag are uselessly discarded.